Exeter–Plymouth line

The Exeter–Plymouth line, also called the South Devon Main Line, is a central part of the trunk railway line between London Paddington and Penzance in the southern United Kingdom. It is a major branch of the Great Western Main Line and runs from Exeter St Davids to Plymouth, from where it continues as the Cornish Main Line. It was one of the principal routes of the Great Western Railway which became part of the Western Region of British Railways in 1948 and is presently operated by Network Rail.

The line between Exeter and Plymouth was built and operated originally by the South Devon Railway Company. It was constructed during the mid-to-late 1840s; its engineering was highly influenced by Isambard Kingdom Brunel, especially in the choice to incorporate a novel atmospheric railway propulsion system. The railway was built in stages, with the first section opening on 30 May 1846. On 25 February 1847, the atmospheric apparatus was used for the first time; all services on the line were operated on the atmospheric system for the first time on 23 February 1848. Months later, it was recognised that the apparatus was struggling and thus the company decided to abandon all use of atmospheric propulsion. Conventional steam locomotives were adopted instead while the atmospheric equipment was deactivated and gradually discarded.

The line was completed in its entity as a traditional railway during 1849. By 1 February 1876, the nominally independent companies in the region had all been amalgamated into the Great Western Railway (GWR); it was converted from broad gauge to standard gauge not long after. The line passed over to the newly-formed British Railways as a result of the GWR's nationalisation on 1 January 1948. The line was upgraded to permit higher top speeds during the 1980s, although it was not electrified as had been proposed. In the mid 1990s, British Rail was privatised, thus the line was transferred to the private railway infrastructure company Railtrack and, after its collapse, its successor company Network Rail.